Advancements in Premier’s Zulu Lithium Project
Premier African Minerals Limited has reported that their lithium project is up and running, producing saleable concentrate. The company is still making improvements to increase both the quality and quantity of output.
Patricia Rwafa
In a previous update in April, Premier announced they were focusing on their Zulu lithium processing unit (flotation circuit). This unit is now operational and producing commercial-grade lithium concentrate (spodumene concentrate). Premier is still fine-tuning the unit to improve the amount and quality of lithium concentrate it produces. They expect ongoing improvements in both areas.
According to George Roach, CEO, “Thanks to the support the Company receives from ENPROTEC, the supplier of the flotation plant components, and innovation and dedication from our team at Zulu, we are now able to run the flotation circuit continuously and produce saleable spodumene concentrate.
There is much to be encouraged by, notably, the use of an activator in the spodumene flotation plant that has seen recoveries in internal laboratory work approaching 90% and indications that the ore body in situ grade is higher than was estimated in our Resource model. The overall plant is currently running at a feed rate to spodumene flotation that is approximately 50% of the original flotation design capacity and will need a further conditioning tank and minor pump upgrades to operate at the full design capacity. This is over and above the recently completed flow changes. The required pumps are already at the site, and the additional civils for the conditioning tank should be completed in May 2024.
Target production for the coming week is expected to start at 50 tonnes of spodumene concentrate per day with increasing production. The target’s full projected capacity remains at 4,000 tonnes per month. Grade is consistently improving with continuous running, and the latest internal chemical analysis of spodumene concentrate produced by the flotation circuit indicates grades have now improved to between 4.5% and 6.3% Li2O,” he said.
The Zulu Plant
For the reasons previously reported, Premier replaced the original plant contractor in March 2024. While the flotation circuit is now running in a constant and stable state, it will take time to fully remedy the original design deficiencies in the overall plant and move from what in many instances are interim fixes to the final operating plant. Some of these issues are set out below:
Ore Sorters
Neither the XRT nor the Ultraviolet sorters are adequately performing the functions for which they were sold and delivered to the Company. It is only the diligent and very careful efforts of a team from the Zulu Geology Department that both carefully oversee mining and ROM pad inspections to avoid waste reporting to the plant and thus allow the plant to operate contaminant-free. This interim solution is working well and is adequate for now but does not represent a long-term solution. The equipment supplier has been called upon to deal with this. Premier will seek to enforce its rights and is investigating alternatives.
Milling and Sizing
The original mill and screen system were inadequate and unable to provide more adequately milled and screened material. This setback Zulu by a year. The new ball mill and sizing equipment have resulted in an interim stable operation but only after a complete redesign of the mill discharge and hydro sizer circuit to operate at a consistent optimized feed rate. Additional upgrades will be installed in this circuit shortly to bring this to industry standard.
Magnetic Separation and Tantalum Recovery
The plant was supplied with a magnetic separator and a circuit intended to remove both a paramagnetic and a magnetic fraction for bagging. The magnetic separator supplied is low intensity (LIMS) and cannot remove a paramagnetic fraction that would include tantalum. The magnetic separator circuit is further unable to efficiently remove iron generated from the milling process to an acceptable degree and will need to be upgraded shortly.
Flotation Circuit
The components of the flotation circuit were originally specified by the original plant contractor on the basis that they would be integrated, installed, and commissioned by them. That ENPROTEC has committed to rectifying design constraints and commissioning this part of the plant is a major factor in the successful operational status now achieved.
Ore Body and Plant Grades
With the development of the open pit, the Company has now been able to validate the actual pegmatite that is being mined. In-pit evaluation is undertaken through the sampling of the pegmatite from blast hole drilling and channel samples cut across the bench. This allows for better reconciliation to the 5m x 5m x 5m Assay Block Model grades. On the bench level currently being developed and mined, the Indicated Resource grade from the assay block model was 1.01% Li2O while the average grade of the ore hauled to the ROM pad is currently 1.13% Li2O, an approximate 10% increase.
At the same time, with material blended from selective mining in the EPO area, Li2O grades recorded in the ore feed to the flotation circuit are in the range of 1.1% Li2O to 1.8% Li2O, and the dry solids being fed to the spodumene float plant contain between 12% and 25% spodumene.
Spodumene Concentrate
The term SC6 is used as a price determination point, being the price paid for spodumene concentrate in which the Li2O grade is 6%. Approximately 74% of the concentrate would then be made up of spodumene. The spodumene concentrate in any grade more than 4% Li2O is saleable with an adjustment to the price paid relative to the actual amount of spodumene contained in that bag. It should be noted that prices are quoted for spodumene concentrates at lower grades and these prices are in the public domain.
It is worth noting that the market for lepidolite is improving, and Premier believes that it is likely that our Mica/lepidolite will sell shortly.
Financial Model
The Company will engage an independent consultancy to assess overall cost implications related to the present mining operation. Previously, the Company has indicated a mine gate production cost of $800 per ton. This may benefit from reduced mining costs linked to ore sourced from within the EPO.